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<html>
<head>
<meta charset="UTF-8">
<title>应用算数运算符计算商品金额</title>
<script language="javascript">
	var price = 19.7;
	var number = 100;
	var sum = price *number;
	window.alert(sum);
	document.write("<h1>This is a heading </h1>");
</script>
</head>
<body>

</body>
</html>